Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a generator, a gearbox, a nacelle, and one or more rotor blades. The rotor blades capture kinetic energy from the wind using known airfoil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
The size, shape, and weight of rotor blades are common factors that contribute to energy efficiencies of wind turbines. An increase in rotor blade size increases the energy production of a wind turbine, while a decrease in weight also furthers the efficiency of the wind turbine. Furthermore, as rotor blade sizes grow, extra attention needs to be given to the structural integrity thereof. Accordingly, efforts to increase rotor blade size and strength aid in the continuing growth of wind turbine technology and the adoption of wind energy as an alternative energy source.
As the size of wind turbines increases, particularly the size of the rotor blades, so do the respective costs of manufacturing, transporting, and assembly of the wind turbines. The economic benefits of increased wind turbine sizes must be weighed against these factors. For example, the costs of pre-forming, transporting, and erecting a wind turbine having large rotor blades may significantly impact the economic advantage of a larger wind turbine.
One known strategy for reducing the costs of pre-forming, transporting, and erecting wind turbines having rotor blades of increasing sizes is to manufacture the rotor blades in blade segments. The blade segments may be assembled to form the rotor blade after, for example, the individual blade segments are transported to an erection location. However, known methods for connecting the blade segments together, such as bonded and bolted joints, have a variety of disadvantages. For example, bonded joints can offer optimum strength and weight for the connecting segments; however, such joints can be complex and difficult to accomplish in the field. In addition, bonded joints may require expensive environmental conditions to be maintained. Though bolted joints can typically be easier to assemble in the field, they are not as efficient at transferring loads from the tip section to the root section of the rotor blade, require materials and weight to be added to the rotor blade, and require long term monitoring and maintenance.
Accordingly, the art is continuously seeking new and improved joint technologies for joining blade segments of rotor blades. More specifically, there is a need for a joint assembly for rotor blade segments that simplifies the assembly thereof.